refactor: networkprotocol, add string / enum conversion methods use them in config and elsewhere

src/lib/base/NetworkProtocol.h

@@ -1,13 +1,62 @@
 /*
  * Deskflow -- mouse and keyboard sharing utility
- * SPDX-FileCopyrightText: (C) 2025 Deskflow Developers
+ * SPDX-FileCopyrightText: (C) 2025 - 2026 Deskflow Developers
  * SPDX-License-Identifier: GPL-2.0-only WITH LicenseRef-OpenSSL-Exception
  */
 
 #pragma once
+#include <QString>
+
+inline static const auto kSynergyProtocolOption = "synergy";
+inline static const auto kBarrierProtocolOption = "barrier";
 
 enum class NetworkProtocol
 {
+  Unknown = -1,
   Synergy,
   Barrier
 };
+
+static int networkProtocolToInt(const NetworkProtocol proto)
+{
+  return static_cast<int>(proto);
+}
+
+static NetworkProtocol networkProtocolFromInt(const int value)
+{
+  return static_cast<NetworkProtocol>(value);
+}
+
+static QString networkProtocolToOption(const NetworkProtocol proto)
+{
+  switch (proto) {
+  case NetworkProtocol::Synergy:
+    return kSynergyProtocolOption;
+  case NetworkProtocol::Barrier:
+    return kBarrierProtocolOption;
+  default:
+    return {};
+  }
+}
+
+static QString networkProtocolToName(const NetworkProtocol proto)
+{
+  switch (proto) {
+  case NetworkProtocol::Synergy:
+    return QStringLiteral("Synergy");
+  case NetworkProtocol::Barrier:
+    return QStringLiteral("Barrier");
+  default:
+    return {};
+  }
+}
+
+static NetworkProtocol networkProtocolFromString(const QString &proto)
+{
+  using enum NetworkProtocol;
+  if (proto.compare(kBarrierProtocolOption, Qt::CaseInsensitive) == 0)
+    return Barrier;
+  if (proto.compare(kSynergyProtocolOption, Qt::CaseInsensitive) == 0)
+    return Synergy;
+  return Unknown;
+}

src/lib/gui/config/ServerConfig.cpp

@@ -160,7 +160,7 @@ void ServerConfig::recall()
 
   haveHeartbeat(settings().value("hasHeartbeat", false).toBool());
   setHeartbeat(settings().value("heartbeat", 5000).toInt());
-  setProtocol(static_cast<NetworkProtocol>(settings().value("protocol", static_cast<int>(protocol())).toInt()));
+  setProtocol(networkProtocolFromInt(settings().value("protocol", networkProtocolToInt(protocol())).toInt()));
   setRelativeMouseMoves(settings().value("relativeMouseMoves", false).toBool());
   setWin32KeepForeground(settings().value("win32KeepForeground", false).toBool());
   haveSwitchDelay(settings().value("hasSwitchDelay", false).toBool());
@@ -220,8 +220,6 @@ int ServerConfig::adjacentScreenIndex(int idx, int deltaColumn, int deltaRow) co
 
 QTextStream &operator<<(QTextStream &outStream, const ServerConfig &config)
 {
-  using enum NetworkProtocol;
-
   outStream << "section: screens" << Qt::endl;
 
   for (const Screen &s : config.screens()) {
@@ -261,13 +259,9 @@ QTextStream &operator<<(QTextStream &outStream, const ServerConfig &config)
   if (config.hasHeartbeat())
     outStream << "\t" << "heartbeat = " << config.heartbeat() << Qt::endl;
 
-  if (config.protocol() == Synergy) {
-    outStream << "\t" << "protocol = synergy" << Qt::endl;
-  } else if (config.protocol() == Barrier) {
-    outStream << "\t" << "protocol = barrier" << Qt::endl;
-  } else {
+  if (config.protocol() == NetworkProtocol::Unknown)
     qFatal("unrecognized protocol when writing config");
-  }
+  outStream << "\t" << "protocol = " << networkProtocolToOption(config.protocol()) << Qt::endl;
 
   outStream << "\t"
             << "relativeMouseMoves = " << (config.relativeMouseMoves() ? "true" : "false") << Qt::endl;

src/lib/gui/dialogs/ServerConfigDialog.cpp

@@ -20,7 +20,6 @@
 #include <QMessageBox>
 
 using enum ScreenConfig::SwitchCorner;
-using enum NetworkProtocol;
 
 ServerConfigDialog::ServerConfigDialog(QWidget *parent, ServerConfig &config)
     : QDialog(parent, Qt::WindowTitleHint | Qt::WindowSystemMenuHint),

src/lib/server/Config.cpp

@@ -25,12 +25,6 @@
 using namespace deskflow::string;
 
 namespace deskflow::server {
-
-// Protocol options used in configuration files (lowercase).
-// Note that @ref kSynergyProtocolName / @ref kBarrierProtocolName use capitalized names.
-const auto kSynergyProtocolOption = "synergy";
-const auto kBarrierProtocolOption = "barrier";
-
 //
 // Config
 //
@@ -1321,15 +1315,10 @@ std::string Config::getOptionValue(OptionID id, OptionValue value)
     return result;
   }
   if (id == kOptionProtocol) {
-    using enum NetworkProtocol;
-    const auto enumValue = static_cast<NetworkProtocol>(value);
-    if (enumValue == Synergy) {
-      return kSynergyProtocolOption;
-    } else if (enumValue == Barrier) {
-      return kBarrierProtocolOption;
-    } else {
+    const auto enumValue = networkProtocolFromInt(value);
+    if (enumValue == NetworkProtocol::Unknown)
       throw InvalidProtocolException();
-    }
+    return networkProtocolToOption(enumValue).toStdString();
   }
 
   return "";
@@ -1808,12 +1797,10 @@ OptionValue ConfigReadContext::parseCorner(const std::string &arg) const
 
 OptionValue ConfigReadContext::parseProtocol(const std::string &args) const
 {
-  if (CaselessCmp::equal(args, kSynergyProtocolOption)) {
-    return static_cast<OptionValue>(NetworkProtocol::Synergy);
-  } else if (CaselessCmp::equal(args, kBarrierProtocolOption)) {
-    return static_cast<OptionValue>(NetworkProtocol::Barrier);
-  }
-  throw ServerConfigReadException(*this, "invalid protocol argument \"%{1}\"", args);
+  const auto protoValue = networkProtocolFromString(QString::fromStdString(args));
+  if (protoValue == NetworkProtocol::Unknown)
+    throw ServerConfigReadException(*this, "invalid protocol argument \"%{1}\"", args);
+  return static_cast<OptionValue>(protoValue);
 }
 
 OptionValue ConfigReadContext::parseCorners(const std::string &args) const

src/lib/server/Server.cpp

@@ -273,13 +273,9 @@ void Server::disconnect()
 
 std::string Server::protocolString() const
 {
-  using enum NetworkProtocol;
-  if (m_protocol == Synergy) {
-    return kSynergyProtocolName;
-  } else if (m_protocol == Barrier) {
-    return kBarrierProtocolName;
-  }
-  throw InvalidProtocolException();
+  if (m_protocol == NetworkProtocol::Unknown)
+    throw InvalidProtocolException();
+  return networkProtocolToName(m_protocol).toStdString();
 }
 
 uint32_t Server::getNumClients() const
@@ -1074,15 +1070,10 @@ void Server::processOptions()
     const OptionID id = optionId;
     const OptionValue value = optionValue;
     if (id == kOptionProtocol) {
-      using enum NetworkProtocol;
-      const auto enumValue = static_cast<NetworkProtocol>(value);
-      if (enumValue == Synergy) {
-        m_protocol = Synergy;
-      } else if (enumValue == Barrier) {
-        m_protocol = Barrier;
-      } else {
+      const auto enumValue = networkProtocolFromInt(value);
+      if (enumValue == NetworkProtocol::Unknown)
         throw InvalidProtocolException();
-      }
+      m_protocol = enumValue;
     } else if (id == kOptionScreenSwitchDelay) {
       m_switchWaitDelay = 1.0e-3 * static_cast<double>(value);
       if (m_switchWaitDelay < 0.0) {